Radiation detection system with surface plasmon resonance detection and related methods

ABSTRACT

A radiation detection system may include a radiation source, and a surface plasmon resonance (SPR) radiation detector. The SPR radiation detector may include a structure, a surface plasmon support material on portions of the structure and configured to receive radiation from the radiation source that initiates a surface plasmon at an interface between the structure and the surface plasmon support material, and a probing device coupled to the structure and configured to detect the surface plasmon.

TECHNICAL FIELD

The present disclosure relates to the field of detection devices, and,more particularly, to a radiation detection device and related methods.

BACKGROUND

X-ray detectors have wide usage in several fields. For example, X-rayimaging is ubiquitous in the medical imaging field. In some industrialapplications, X-ray imaging, i.e. radiography, is used to verify themechanical integrity and fidelity of components.

Once such example application is verifying the structural integrity ofaboveground pipelines for transferring hydrocarbon resources. Sincethese pipelines span many miles, the inspection device is necessarilymobile. Indeed, since these aboveground pipes are exposed to wideenvironmental extremes, they are inspected regularly for leaks.

In one approach to inspecting these pipelines, personnel use mobilescintillator-based X-ray detectors to image individual pipeline joints.This approach has drawbacks since the scintillator-based X-ray detectorsare quite fragile and expensive.

In another approach, a pigging device is fed through the pipeline. Thepigging device may include an X-ray imaging device. Again, the expenseand fragility of the scintillator-based X-ray detectors can be a problemin this approach.

SUMMARY

Generally speaking, a radiation detection system may comprise aradiation source, and a surface plasmon resonance (SPR) radiationdetector comprising at least one structure, and a surface plasmonsupport material on portions of the at least one structure. The surfaceplasmon support material may be configured to receive radiation from theradiation source that initiates a surface plasmon at an interfacebetween the at least one structure and the surface plasmon supportmaterial. The radiation detection system may comprise a probing devicecoupled to the at least one structure and configured to detect thesurface plasmon.

For example, the at least one structure may comprise one of a ringshaped-structure, a sphere-shaped structure, a linear structure, or aplate-shaped structure. Also, the at least one structure may include amaterial transparent to at least one of ultraviolet (UV), visible, andinfrared (IR) radiation. More specifically, the probing device maycomprise a probe electromagnetic (EM) radiation source configured toemit probe EM radiation into the at least one structure. The probe EMradiation may interact with the surface plasmon and generate new EMradiation having a different wavelength than the probe EM radiationresulting from the interaction. The probing device may comprise an EMradiation detector coupled to the at least one structure and configuredto detect the new EM radiation. The probing device may also include aprocessor configured to determine a wavelength of the new EM radiation.

For example, the probe EM radiation source may comprise at least one ofa visible EM radiation source, a UV EM radiation source, and an IR EMradiation source. The EM radiation detector may comprise at least onephotodiode. Also, the EM radiation detector may comprise at least oneenergy sensitive detector, or at least one energy integrating detector.

For example, the surface plasmon support material may comprise at leastone transition metal. The surface plasmon support material may compriseat least one of gold, silver, aluminum, aluminum-silver alloy, dopedsemiconductors, silicon carbide, diamond, copper, copper-tungsten, andtopological insulators. The radiation source may be configured to emitat least one of X-ray radiation, gamma radiation, neutron radiation,beta particle radiation, proton particle radiation, and alpha particleradiation.

In particular, the probing device may be configured to detect differentradiation frequencies and intensities based upon a non-linear4-wave/2-wave mixed beam resulting from different surface plasmonfrequencies and intensities, different probe beam frequencies, anddifferent probe beam angles at an interface between the at least onestructure and the surface plasmon support material. In some embodiments,the radiation source may comprise a radiation emitter, and the radiationemitter may be configured to irradiate an object. The object maytransmit or scatter the radiation, and the SPR radiation detector may beconfigured to detect the transmitted or scattered radiation.

Another aspect is directed to a SPR radiation detector comprising atleast one structure, and a surface plasmon support material on portionsof the at least one structure and configured to receive radiation from aradiation source that initiates a surface plasmon at an interfacebetween the at least one structure and the surface plasmon supportmaterial. The SPR radiation detector may include a probing devicecoupled to the at least one structure and configured to detect thesurface plasmon.

Yet another aspect is directed a method of operating a radiationdetection system comprising a radiation source, and a SPR radiationdetector. The SPR radiation detector may comprise at least onestructure, a surface plasmon support material on portions of the atleast one structure, and a probing device coupled to the at least onestructure. The method may comprise receiving radiation at the surfaceplasmon support material from the radiation source that initiates asurface plasmon at an interface between the at least one structure andthe surface plasmon support material, and operating the SPR radiationdetector to detect the surface plasmon.

Another aspect is directed to a method for making a radiation detectionsystem comprising positioning a radiation source, and forming a surfaceplasmon support material on portions of at least one structure and toreceive radiation from the radiation source that initiates a surfaceplasmon at an interface between the at least one structure and thesurface plasmon support material. The method may comprise coupling aprobing device to the at least one structure and configured to detectthe surface plasmon.

Another aspect is directed to a radiation detection system including aradiation source, and a SPR radiation detector. The SPR radiationdetector may include at least one fiber, a surface plasmon supportmaterial on portions of the at least one fiber and configured to receiveradiation from the radiation source that initiates a surface plasmon atan interface between the at least one fiber and the surface plasmonsupport material, and a probing device coupled to the at least one fiberand configured to detect the surface plasmon.

In some embodiments, the at least one fiber may comprise a pluralitythereof arranged in a bundle, and the probing device may comprise aprocessor configured to generate a pixelated image based upon surfaceplasmon detection signals. The plurality of fibers may generate aplurality of signals, and a respective signal from each fiber may definea pixel in the pixelated image.

In some embodiments, the surface plasmon support material may be on asingle end portion of the at least one fiber. Moreover, the at least onefiber may have an end face canted at a non-orthogonal angle to alongitudinal axis of the at least one fiber. Alternatively, the at leastone fiber may have an end face at an orthogonal angle to thelongitudinal axis of the at least one fiber. In other embodiments, thesurface plasmon support material may be on sides substantially parallelto a longitudinal axis of the at least one fiber. In some embodiments,the surface plasmon support material may include a plurality ofdifferent material layers, each different material layer to absorbradiation at a different energy level.

For instance, the at least one fiber may comprise at least one of amulti-mode fiber, a single mode fiber, and a photonic crystal fiber. Theat least one fiber may comprise a material transparent to at least oneof UV, visible, and IR radiation. The material may comprise glass,plastic, polymer, ceramic, silicon carbide, and crystals.

Another aspect is directed to a SPR radiation detector. The SPRradiation detector may include at least one fiber, and a surface plasmonsupport material on portions of the at least one fiber. The surfaceplasmon support material may be configured to receive radiation from aradiation source that initiates a surface plasmon at an interfacebetween the at least one fiber and the surface plasmon support material.The SPR radiation detector may comprise a probing device coupled to theat least one fiber and configured to detect the surface plasmon.

Another aspect is directed to a method of operating a radiationdetection system comprising a radiation source, and a SPR radiationdetector. The SPR radiation detector may include at least one fiber, asurface plasmon support material on portions of the at least one fiber,and a probing device coupled to the at least one fiber. The method maycomprise receiving radiation at the surface plasmon support materialfrom the radiation source that initiates a surface plasmon at aninterface between the at least one fiber and the surface plasmon supportmaterial, and operating the SPR radiation detector to detect the surfaceplasmon.

Yet another is directed to a method for making a radiation detectionsystem. The method may comprise positioning at least one fiber toreceive radiation from a radiation source, forming a surface plasmonsupport material on portions of the at least one fiber and to receivethe radiation from the radiation source that initiates a surface plasmonat an interface between the at least one fiber and the surface plasmonsupport material, and coupling a probing device to the at least onefiber and to detect the surface plasmon, thereby defining a surfaceplasmon resonance (SPR) radiation detector.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a hydrocarbon pipeline inspectionsystem with a radiation detection system, according to the presentdisclosure.

FIG. 2 is a schematic diagram of a first example embodiment of aradiation detection device, according to the present disclosure.

FIG. 3 is a schematic diagram of a second example embodiment of aradiation detection device, according to the present disclosure.

FIG. 4 is a schematic diagram of a third example embodiment of aradiation detection device, according to the present disclosure.

FIG. 5 is a schematic diagram of a fourth example embodiment of theradiation detection device, according to the present disclosure.

FIG. 6 is a schematic diagram of a fifth example embodiment of theradiation detection system, according to the present disclosure.

FIG. 7 a schematic cross-sectional view of another embodiment of thefiber in the radiation detection device, according to the presentdisclosure.

FIG. 8 is a schematic diagram of a sixth embodiment of a radiationdetection device, according to the present disclosure.

FIG. 9 is a flowchart of a method of operating the radiation detectionsystem, according to the present disclosure.

DETAILED DESCRIPTION

The present disclosure will now be described more fully hereinafter withreference to the accompanying drawings, in which several embodiments ofthe invention are shown. This present disclosure may, however, beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein. Rather, these exemplary embodimentsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the present disclosure to those skilledin the art. Like numbers refer to like elements throughout, and base 100reference numerals are used to indicate similar elements in alternativeembodiments.

Referring initially to FIGS. 1-2, a hydrocarbon pipeline inspectionsystem 10 according to the present disclosure is now described. Thehydrocarbon pipeline inspection system 10 illustratively includes apipeline 25 carrying hydrocarbon resources within, and extending above aground surface 27, and a plurality of supports 26 a-26 b affixed to theground surface. As will be appreciated, the pipeline 25 may include aplurality of pipe sections with threaded ends, and the pipeline 25 mayextend over long distances, such as, greater than 1 mile. To assure thestructural integrity of the pipeline 25, the hydrocarbon pipelineinspection system 10 illustratively includes a radiation detectionsystem 24 for imaging the pipe sections as the radiation detectionsystem moves along the outside of the pipeline 25. The imaging of thepipe sections may allow for detection of hairline fractures, which canpredict future leaks. Spectrally, the radiation detection system 24 mayoperate on radiation comprising at least one of X-ray radiation (as inthe illustrated example), gamma radiation, beta particle radiation,proton particle radiation, and alpha particle radiation. Although theillustrated embodiment travels along the outside of the pipeline 25, inother embodiments, the radiation detection system 24 may travel withinthe pipeline in a pigging device (FIG. 8). It should be appreciated thatalthough the illustrated embodiment may operate within the X-rayspectrum, this is merely one option from the several radiation frequencyranges and particle types noted above.

Moreover, it should be appreciated that the hydrocarbon application ismerely exemplary, and that the herein described radiation detectionsystem 24 may be used in many other applications where radiation imagingis needed. Indeed, the radiation detection system 24 may be used forradiation detection in harsh environments (e.g. extreme high/lowtemperatures, sandy areas, windy applications, and high radiationlevels), subsea detection applications, cargo inspections, solar flaredetection, space applications, and orbital satellite applications, andsecurity detection applications.

Referring now to FIG. 2, a radiation detection system 124 illustrativelycomprises a radiation source 111, and a SPR radiation detector 112comprising a structure 114, and a surface plasmon support material 115on portions of the structure. The surface plasmon support material 115is configured to receive radiation from the radiation source 111 thatinitiates a surface plasmon at an interface between the structure 114and the surface plasmon support material. The radiation detection system124 illustratively includes a probing device 113 coupled to thestructure 114 and configured to detect the surface plasmon.

For example, the structure 114 may comprise a plurality of structures insome embodiments. (FIGS. 5-6). In some imaging embodiments, thestructure 114 comprises one or more fibers. (FIGS. 4-6). For example,the fiber may comprise an optical fiber, or a fiber transmittingnon-optical frequencies. For instance, the structure may comprise asphere (FIG. 3), a linear structure, or a ring (FIG. 8). Indeed, theonly requirement for the structure 114 is to transport the probe beam tothe interface between the structure and the surface plasmon supportmaterial 115. This is because of the action of the X-ray radiationinitiating the plasmon, the surface plasmon support structure supportingthe surface plasmon, and the structure carrying the probe beam.

Referring to FIG. 3, another embodiment of the radiation detectionsystem 224 is now described. In this embodiment of the radiationdetection system 224, those elements already discussed above withrespect to FIG. 2 are incremented by 200 and most require no furtherdiscussion herein. This embodiment differs from the previous embodimentin that this radiation detection system 224 illustratively includes thestructure comprising a sphere 214. The surface plasmon support material215 is carried on the external surface of the sphere 214, and theprobing device 213 is carried internally. Advantageously, the radiationdetection system 224 is capable of detecting radiationomnidirectionally.

Referring to FIG. 4, another embodiment of the radiation detectionsystem 324 is now described. In this embodiment of the radiationdetection system 324, those elements already discussed above withrespect to FIGS. 2-3 are incremented by 300 and most require no furtherdiscussion herein. This embodiment differs from the previous embodimentin that this radiation detection system 324 illustratively includes aradiation source 311, and a SPR radiation detector 312. The SPRradiation detector 312 illustratively includes a single fiber 314, and asurface plasmon support material 315 attached to an end face of thefiber and configured to receive radiation from the radiation source 311.

When the surface plasmon support material 315 receives radiation fromthe radiation source 311, a surface plasmon is initiated at an interfacebetween the fiber 314 and the surface plasmon support material 315. TheSPR radiation detector 312 illustratively includes a probing device 313coupled to the fiber 314 and configured to detect the surface plasmon.

Each fiber 314 may comprise an optical fiber in some embodiments. Aswill be appreciated by those skilled in the art, the probing device 313may utilize non-optical frequencies bands, such as submillimeterradiation (e.g., radiation in the Terahertz frequency spectrum).

As shown with solid lines, the radiation source 311 may comprise aninherently radioactive emitter (e.g. a naturally radioactive material),and the SPR radiation detector 312 is configured to receive radiationfrom the inherently radioactive emitter. In other applications, such asan application to image an object 316 (indicated with dashed lines), theradiation source 311 comprises a powered radiation emitter. Someembodiments (FIGS. 5-6) where the fiber 314 comprises a pluralitythereof may be advantageous for imaging the object 316, permittingimaging of the object 316. The radiation emitter would be configured toirradiate the object 316, with the object absorbing, reflecting,transmitting, and scattering the radiation. The SPR radiation detector312 is configured to detect the transmitted and scattered radiation.

It also should be appreciated that the fiber 314 structure is merelyexemplary. In other embodiments, the SPR radiation detector 312 mayalternatively include at least one structure configured to receiveradiation from the radiation source 311. (FIG. 2).

Another aspect is directed to a SPR radiation detector 312. The SPRradiation detector 312 includes a fiber 314 to receive radiation from aradiation source 311, and a surface plasmon support material 315 onportions of the fiber and configured to receive the radiation from theradiation source that initiates a surface plasmon at an interfacebetween the fiber and the surface plasmon support material. The SPRradiation detector 312 further comprises a probing device 313 coupled tothe fiber 314 and configured to detect the surface plasmon.

Another aspect is directed to a method for making a radiation detectionsystem 324. The method includes positioning at least one fiber 314 toreceive radiation from a radiation source 311, and forming a surfaceplasmon support material 315 on portions of the at least one fiber andto receive radiation from the radiation source that initiates the atleast one surface plasmon at an interface between the at least one fiberand the surface plasmon support material. The method includes coupling aprobing device 313 to the at least one fiber 314 and to detect thesurface plasmon, thereby defining a SPR radiation detector.

In some embodiments, the forming of the surface plasmon support material315 comprises at least one of physical vapor deposition (PVD), plating,additive manufacturing, and ultrasonic bonding. The PVD process maycomprise, for example, evaporation, sputtering, chemical vapordeposition (CVD), etc.

Referring now briefly and additionally to FIG. 9, a flowchart 30describes another aspect of the present disclosure. This aspect isdirected to a method of operating a radiation detection system 324comprising a radiation source 311, and a SPR radiation detector 312. TheSPR radiation detector 312 includes at least one fiber 314, at least onesurface plasmon support material 315 on portions of the at least onefiber, and at least one probing device 313 coupled to the at least onefiber. The method comprises receiving radiation at the surface plasmonsupport material 315 from the radiation source 311 that initiates asurface plasmon at an interface between the fiber 314 and the surfaceplasmon support material, and operating the SPR radiation detector 312to detect the surface plasmon. (Blocks 31-35).

Referring now additionally to FIG. 5, another embodiment of theradiation detection system 424 is now described. In this embodiment ofthe radiation detection system 424, those elements already discussedabove with respect to FIGS. 2-4 are incremented by 400 and most requireno further discussion herein. In this illustration, an object 416 isbeing irradiated, but it should be appreciated that this embodimentcould be used in an application where the radiation source 411 comprisesan inherently radioactive source and there are no objects between theinherently radioactive source and the SPR radiation detector 412.

The radiation detection system 424 illustratively includes a radiationsource 411 (e.g. radioisotope, X-ray tube, synchrotron) configured toemit radiation 417 at the object 416 (e.g. a pipe section in FIG. 1),and a SPR radiation detector 412. The radiation source 411 may beconfigured to emit at least one of X-ray radiation, gamma radiation,neutron radiation, beta particle radiation, and alpha particleradiation.

The SPR radiation detector 412 illustratively includes a plurality offibers 414 a-414 e arranged in a bundle to receive scattered and/ortransmitted radiation from the object 416. In the schematic illustratedembodiment, the bundle comprises five fibers 414 a-414 e, but it shouldbe appreciated that the array can be three-dimensional with a largenumber of fibers. Each of the fibers 414 a-414 e illustratively includesa core 422 a-422 e, and a cladding 423 a-423 e surrounding the core.

In the illustrated exemplary embodiment, each of the plurality of fibers414 a-414 e is a single mode fiber. In other embodiments, each of theplurality of fibers 414 a-414 e comprises a multi-mode fiber or aphotonic crystal fiber.

The SPR radiation detector 412 illustratively includes a surface plasmonsupport material 415 a-415 e on portions of the plurality of fibers 414a-414 e. In all embodiments, the surface plasmon support material 415a-415 e may comprise a material having a non-linear third ordersusceptibility. Alternatively, the surface plasmon support material 415a-415 e may comprise a material having a non-linear second ordersusceptibility.

In some embodiments, the surface plasmon support material 415 a-415 emay comprise a transition metal. For example, the surface plasmonsupport material 415 a-415 e may include at least one of a transitionmetal, gold, silver, aluminum, aluminum-silver alloy, dopedsemiconductors, silicon carbide, diamond, copper, copper-tungsten, andtopological insulators (e.g. Bi₂Se₃).

In the illustrated embodiment, the surface plasmon support material 415a-415 e is formed only on a single end portion/face of each fiber fromthe plurality of fibers 414 a-414 e. Of course, in other embodiments(FIG. 7), the surface plasmon support material 415 a-415 e may extendalternatively or additionally along other portions of the plurality offibers 414 a-414 e.

In the illustrated embodiment, each of the plurality of fibers 414 a-414e has an end face at an orthogonal angle (or substantially orthogonalangle comprising 90°±5° to a longitudinal axis of a respective fiber. Inother embodiments (noted with dashed line in FIG. 7), each of theplurality of fibers 414 a-414 e has an end face canted at anon-orthogonal angle (α) to the longitudinal axis of a respective fiber.Helpfully, this canted cleaved end face may provide for enhanced signalstrength of the returned probe beam carrying the signal indicative ofthe plasmonic wave (or of the surface plasmon wave-altered EM radiationω_(new)).

The SPR radiation detector 412 illustratively includes a probing device413 a-413 e coupled to the plurality of fibers 414 a-414 e. The probingdevice 413 a-413 e is configured to emit source EM radiation ω_(probe)into the plurality of fibers 414 a-414 e. The source EM radiationω_(probe) may comprise any form of radiation capable of traveling down afiber with low loss, such as, at least one of visible radiation, UVradiation, and IR radiation. After interacting with the surface plasmonat the interface between the surface plasmon support material 415 a-415e and the fiber 414 a-414 e, the probe beam wavelengths are shifted.

The EM radiation detector (not shown) in the probing device 413 a-413 eis responsive to the surface plasmon wave-altered EM radiation ω_(new).In particular, the probing device 413 a-413 e is configured to determinewhen SPR is present at the interface between the surface plasmon supportmaterial 415 a-415 e and the end portions of the one or more fibers 414a-414 e.

In the illustrated embodiment, there is one probing device 413 a-413 efor each fiber 414 a-414 e. In other embodiments, the number of SPRdetector circuitries 413 a-413 e may be reduced using opticalmultiplexing techniques.

Another aspect is directed to a SPR radiation detector 412. The SPRradiation detector 412 includes a plurality of fibers 414 a-414 earranged in a bundle to receive transmitted and/or scattered radiationfrom an object 416, a surface plasmon support material 415 a-415 e onportions of the plurality of fibers, and a probing device 413 a-413 ecoupled to the plurality of fibers and responsive to the transmittedand/or scattered radiation.

Referring to FIG. 6, another embodiment of the radiation detectionsystem 524 is now described. In this embodiment of the radiationdetection system 524, those elements already discussed above withrespect to FIG. 5 are incremented by 500 and most require no furtherdiscussion herein. This embodiment differs from the previous embodimentin that this radiation detection system 524 illustratively includes theprobing device 513 a-513 e comprising an EM radiation source 519configured to emit probe EM radiation ω_(probe) into the plurality offibers 514 a-514 e.

In particular, when the transmitted and/or scattered radiation from theobject 516 impacts the surface plasmon support material 515 a-515 e,surface plasmons are generated at the surface plasmon supportmaterial-fiber interface. This action is based upon the electronsliberated from atoms in the surface plasmon support material 515 a-515 eby the impacting radiation from the object 516. The probe EM radiationω_(probe) interacts with the surface plasmons in the surface plasmonsupport material 515 a-515 e at the interface with the fiber 514 a-514 eand is changed during these interactions. In other words, the probe EMradiation ω_(probe) interacts with the surface plasmons and new EMradiation ω_(new) is generated having a different wavelength than theprobe EM radiation resulting from the interaction via 4-wave or 2-wavemixing at the fiber/surface plasmon support material interface.

Further, the probing device 513 a-513 e may be configured to detectdifferent radiation frequencies and intensities impacting the surfaceplasmon support material 515 a-515 e. This determination is based upon asurface plasmon frequency, its intensity, and the frequency andintensity of a 4-wave or 2-wave mixed beam detected by the probingdevice 513 a-513 e.

The probing device 513 a-513 e illustratively includes an EM radiationdetector 518 adjacent to the plurality of fibers 514 a-514 e andconfigured to detect the new EM radiation ω_(new). Additionally, the EMradiation detector 518 comprises one or more photodiode detectors (e.g.arranged in an array). In other embodiments, the EM radiation detector518 comprises at least one of a photodiode, an energy sensitivedetector, and an energy integrating detector. The probing device 513a-513 e illustratively includes a processor 520 configured to determinea wavelength shift (i.e. a new wavelength) of the new EM radiationω_(new).

For example, each fiber 514 a-514 e may comprise a glass material, butthis material can be varied. In particular, each fiber 514 a-514 e maycomprise at least one from the following: a material transparent in oneor more of the frequency ranges of UV, visible, and IR; a glassmaterial; a plastic material; a polymer; a ceramic transparent in one ormore of the frequency ranges UV, visible, and IR; silicon carbide; and acrystal (e.g. calcite) transparent in one or more of the frequencyranges UV, visible, and IR. As will be appreciated, the wavelength andintensity of the probe EM radiation 519 and the wavelength and intensityof the surface plasmon wave-altered EM radiation ω_(new) may changebased upon the inherent optical properties of the fiber 514 a-514 e andsurface plasmon support materials, requiring an alteration in theprocessor 520 parameters.

The radiation detection system 524 illustratively includes a display 529coupled to the processor 520. The processor is configured to arrangeoutputs from the plurality of fibers 514 a-514 e into a photon-sensitivearray to define a pixelated image for presentation on the display 529.The plurality of fibers 514 a-514 e generates a plurality of photonsignals defining the pixelated image. Advantageously, the radiationdetection system 512 may be fit into a portable package, as compared totypical scintillator approaches. For example, the bundle of fibers 514a-514 e may be arranged into a 4,000×4,000 square imaging array. In anexample embodiment, each fiber 514 a-514 e has a pixel width of 10 μm(single mode fiber example) and the imaging array has a size of 40 cm×40cm. In some embodiments, the radiation detection system 524illustratively includes a memory configured to store the image. Also, inthis embodiment, each of the plurality of fibers 514 a-514 e may be amulti-mode fiber or each may be a single mode fiber.

Referring now additionally to FIG. 7, another embodiment of theradiation detection system 624 is now described. In this embodiment ofthe radiation detection system 624, those elements already discussedabove with respect to FIGS. 5-6 are incremented by 600 and most requireno further discussion herein. This embodiment differs from the previousembodiment in that this radiation detection system 624 has the surfaceplasmon support material 615 comprising additional layers 621 a-621 cfurther extending on sides of the plurality of fibers 614. Also, theadditional layers 621 a-621 c of the surface plasmon support material615 may be on sides substantially parallel (±10° of parallel) to alongitudinal axis 628 of the at least one fiber.

In an alternate embodiment, the additional layers 621 a-621 c of thesurface plasmon support material 615 may comprise materials havingefficient absorption at different x-ray wavelengths. Each layerthickness is determined by a trade-off between radiation absorptionefficiency and the ability of the surface plasmonic electric field ineach layer to penetrate the other layers to interact with the fiberoptic electric field and create a surface plasmon wave in the surfaceplasmon support layer. For example, erbium absorbs efficiently atapproximately 57 keV, while ytterbium absorbs efficiently atapproximately 61 keV. Layering the materials with the ytterbium situatedbetween the fiber optic material and the erbium layer enables the 57 keVx-rays to be absorbed in the erbium and potentially creating a surfaceplasmon wave if the surface plasmon wave can penetrate all the waythrough the ytterbium layer and interact with the dielectric material ofthe fiber optic. The higher energy x-rays travel through the erbium andare absorbed in the ytterbium, creating a surface plasmon wave at theytterbium/fiber interface. Making the ytterbium layer thinner than thepenetration depth of the erbium surface plasmon field, may enableexistence of the erbium surface plasmon wave in the erbium layer and bevisible by the probe beam at the fiber/plasmon support materialinterface.

Referring now additionally to FIG. 8, another embodiment of theradiation detection system 724 is now described. In this embodiment ofthe radiation detection system 724, those elements already discussedabove with respect to FIGS. 5-7 are incremented by 700 and most requireno further discussion herein. This embodiment differs from the previousembodiment in that this radiation detection system 724 has the structurecomprising a ring-shaped structure 714, and the surface plasmon supportmaterial 715 is carried on an outer radial surface of the ring-shapedstructure. Indeed, the shape of the radiation detector system would behelpful in pigging device applications, for example. In someembodiments, the surface plasmon support material 715 may be carriedadditionally or alternatively on an inner radial surface of thering-shaped structure 714. Is should be appreciated that thecircle-shaped ring is merely exemplary, and other shapes are possible,such as oval shapes, rectangle-shapes, etc.

Advantageously, the radiation detection system 124, 224, 324, 424, 524,624, 724 may provide an approach to the problems of prior art radiationdetectors. Firstly, the SPR radiation detector 112, 212, 312, 412, 512,712 has lower manufacturing costs and reduced size weight and power(SWaP). Moreover, since the SPR radiation detector 112, 212, 312, 412,512, 712 is mechanically robust, it has a wider field deployability. Inshort, this radiation detection system 124, 224, 324, 424, 524, 624, 724is readily portable.

Moreover, the disclosed embodiments (i.e. the pixelated imagingembodiments of FIGS. 5-6) may improve on the coarse resolution of priorart approaches. In those approaches, the X-ray detector active pixelsize may be 50 microns or larger. Positively, the SPR radiation detector412, 512 may have an active pixel size in the range of 1-5 microns foreach fiber 414A-414 e, 514 a-514 e in the bundle. Yet further, since theSPR radiation detector 112, 212, 312, 412, 512, 712 down-converts thereceived radiation to UV, visible, or IR EM radiation, the SPR radiationdetector 112, 212, 312, 412, 512, 712 may utilize less expensivedetection equipment than the direct-conversion radiation detectorapproaches and may be simpler to fabricate than the scintillator-baseddetectors.

Helpfully, the radiation detection system 124, 224, 324, 424, 524, 624,724 may provide improved radiation detection sensitivity. Indeed, thesensitivity may be on the order of a solid state single-photon-countingsemiconductor device.

Also, the radiation detection system 124, 224, 324, 424, 524, 624, 724may be structured for enhanced durability. In particular, the probingdevice 113, 213, 313, 413 a-413 e, 513 a-513 e, 513 a-513 e contains theonly electronic circuitry for the SPR radiation detector 112, 212, 312,412, 512, 712, and these components can be readily shielded fromradiation damage by remoting the electronic circuitry out of the directradiation bombardment path. Moreover, due to the low loss quality of theplurality of fibers 314, 414 a-414 e, 514 a-514 e, the probing signalscan be remoted over long distances. Of course, this is in contrast totypical solid state approaches where the read circuitry may beintegrated with the sensing components, putting them in line-of-sight ofbombardment by the radiation source, preventing them from being shieldedeffectively. Indeed, in typical scintillator approaches, the electroniccircuitry is placed directly behind the scintillator and impacted byhigh energy radiation that is not absorbed by the scintillator.

Other features relating to radiation detection systems are disclosed inco-pending application: titled “RADIATION DETECTION SYSTEM WITH SURFACEPLASMON RESONANCE DETECTION AND RELATED METHODS,” Attorney Docket No.GCSD-2991 (62521), which is incorporated herein by reference in itsentirety.

Many modifications and other embodiments of the present disclosure willcome to the mind of one skilled in the art having the benefit of theteachings presented in the foregoing descriptions and the associateddrawings. Therefore, it is understood that the present disclosure is notto be limited to the specific embodiments disclosed, and thatmodifications and embodiments are intended to be included within thescope of the appended claims.

That which is claimed is:
 1. A radiation detection system comprising: aradiation source; and a surface plasmon resonance (SPR) radiationdetector comprising at least one fiber, a surface plasmon supportmaterial on portions of said at least one fiber and configured toreceive radiation from said radiation source that initiates a surfaceplasmon at an interface between said at least one fiber and said surfaceplasmon support material, and a probing device coupled to said at leastone fiber and configured to detect the surface plasmon.
 2. The radiationdetection system of claim 1 wherein said probing device comprises: aprobe electromagnetic (EM) radiation source configured to emit probe EMradiation into said at least one fiber, the probe EM radiationinteracting with the surface plasmon and generating new EM radiationhaving a different wavelength than the probe EM radiation resulting fromthe interaction; and an EM radiation detector coupled to said at leastone fiber and configured to detect the new EM radiation.
 3. Theradiation detection system of claim 2 wherein said probing devicecomprises a processor configured to determine a wavelength of the new EMradiation.
 4. The radiation detection system of claim 2 wherein saidprobe EM radiation source comprises at least one of a visible EMradiation source, an ultraviolet (UV) EM radiation source, and aninfrared (IR) EM radiation source.
 5. The radiation detection system ofclaim 2 wherein said EM radiation detector comprises at least onephotodiode.
 6. The radiation detection system of claim 2 wherein said EMradiation detector comprises at least one energy sensitive detector. 7.The radiation detection system of claim 2 wherein said EM radiationdetector comprises at least one energy integrating detector.
 8. Theradiation detection system of claim 1 wherein said at least one fibercomprises a plurality thereof arranged in a bundle; and wherein saidprobing device comprises a processor configured to generate a pixelatedimage based upon surface plasmon detection signals, the plurality offibers generating a plurality of signals, a respective signal from eachfiber defining a pixel in the pixelated image.
 9. The radiationdetection system of claim 1 wherein said surface plasmon supportmaterial comprises at least one transition metal.
 10. The radiationdetection system of claim 1 wherein said surface plasmon supportmaterial comprises at least one of gold, silver, aluminum,aluminum-silver alloy, doped semiconductors, silicon carbide, diamond,copper, copper-tungsten, and topological insulators.
 11. The radiationdetection system of claim 1 wherein said surface plasmon supportmaterial is on a single end portion of said at least one fiber.
 12. Theradiation detection system of claim 1 wherein said at least one fiberhas an end face canted at a non-orthogonal angle to a longitudinal axisof said at least one fiber.
 13. The radiation detection system of claim1 wherein said at least one fiber has an end face at an orthogonal angleto a longitudinal axis of said at least one fiber.
 14. The radiationdetection system of claim 1 wherein said surface plasmon supportmaterial is on sides substantially parallel to a longitudinal axis ofsaid at least one fiber; and wherein said surface plasmon supportmaterial comprises a plurality of different material layers, eachdifferent material layer to absorb radiation at a different energylevel.
 15. The radiation detection system of claim 1 wherein said atleast one fiber comprises at least one of a multi-mode fiber, a singlemode fiber, and a photonic crystal fiber.
 16. The radiation detectionsystem of claim 1 wherein said at least one fiber comprises a materialtransparent to at least one of UV, visible, and IR radiation.
 17. Theradiation detection system of claim 16 wherein said material comprisesglass, plastic, polymer, ceramic, silicon carbide, and crystals.
 18. Theradiation detection system of claim 1 wherein said radiation source isconfigured to emit at least one of X-ray radiation, gamma radiation,neutron radiation, beta particle radiation, proton particle radiation,and alpha particle radiation.
 19. The radiation detection system ofclaim 1 wherein said probing device is configured to detect differentradiation frequencies and intensities based upon a 4-wave mixed beamresulting from different surface plasmon frequencies and intensities anddifferent probe beam frequencies.
 20. The radiation detection system ofclaim 1 wherein said probing device is configured to detect differentradiation frequencies and intensities based upon a 2-wave mixed beamresulting from different surface plasmon frequencies and intensities anddifferent probe beam frequencies.
 21. The radiation detection system ofclaim 1 wherein said radiation source comprises a radiation emitter;wherein said radiation emitter is configured to irradiate an object;wherein the object transmits or scatters the radiation; and wherein saidSPR radiation detector is configured to detect transmitted or scatteredradiation.
 22. The radiation detection system of claim 1 wherein saidsurface plasmon support material comprises a plurality of differentmaterial layers, each different material layer to absorb radiation at adifferent energy level.
 23. A surface plasmon resonance (SPR) radiationdetector comprising: at least one fiber; a surface plasmon supportmaterial on portions of said at least one fiber; said surface plasmonsupport material configured to receive radiation from a radiation sourcethat initiates a surface plasmon at an interface between said at leastone fiber and said surface plasmon support material; and a probingdevice coupled to said at least one fiber and configured to detect thesurface plasmon.
 24. The SPR radiation detector of claim 23 wherein saidprobing device comprises: a probe electromagnetic (EM) radiation sourceconfigured to emit probe EM radiation into said at least one fiber, theprobe EM radiation interacting with the surface plasmon and generatingnew EM radiation having a different wavelength than the probe EMradiation resulting from the interaction; and an EM radiation detectorcoupled to said at least one fiber and configured to detect the new EMradiation.
 25. The SPR radiation detector of claim 24 wherein saidprobing device comprises a processor configured to determine a newwavelength of the new EM radiation.
 26. The SPR radiation detector ofclaim 24 wherein said probe EM radiation source comprises at least oneof a visible EM radiation source, an ultraviolet (UV) EM radiationsource, and an infrared (IR) EM radiation source.
 27. The SPR radiationdetector of claim 24 wherein said EM radiation detector comprises atleast one photodiode.
 28. The SPR radiation detector of claim 24 whereinsaid EM radiation detector comprises at least one energy sensitivedetector having at least one pixel.
 29. The SPR radiation detector ofclaim 24 wherein said EM radiation detector comprises at least oneenergy integrating detector having at least one pixel.
 30. The SPRradiation detector of claim 23 wherein said surface plasmon supportmaterial comprises at least one transition metal.
 31. The SPR radiationdetector of claim 23 wherein said surface plasmon support materialcomprises at least one of gold, silver, aluminum, aluminum-silver alloy,doped semiconductors, silicon carbide, diamond, copper, copper-tungsten,and topological insulators.
 32. The SPR radiation detector of claim 23wherein said surface plasmon support material is on a single end portionof said at least one fiber.
 33. The SPR radiation detector of claim 23wherein said surface plasmon support material is on sides substantiallyparallel to a longitudinal axis of said at least one fiber; and whereinsaid surface plasmon support material comprises a plurality of differentmaterial layers, each different material layer to absorb radiation at adifferent energy level.
 34. The SPR radiation detector of claim 23wherein said surface plasmon support material comprises a plurality ofdifferent material layers, each different material layer to absorbradiation at a different energy level.
 35. A method of operating aradiation detection system comprising a radiation source, and a surfaceplasmon resonance (SPR) radiation detector, the SPR radiation detectorcomprising at least one fiber, a surface plasmon support material onportions of the at least one fiber, and a probing device coupled to theat least one fiber, the method comprising: receiving radiation at thesurface plasmon support material from the radiation source thatinitiates a surface plasmon at an interface between the at least onefiber and the surface plasmon support material; and operating the SPRradiation detector to detect the surface plasmon.
 36. The method ofclaim 35 further comprising: operating a probe electromagnetic (EM)radiation source to emit probe EM radiation into said at least onefiber, the probe EM radiation interacting with the surface plasmon andgenerating new EM radiation having a different wavelength than the probeEM radiation resulting from the interaction; and operating an EMradiation detector coupled to said at least one fiber, the EM radiationdetector to detect the new EM radiation.
 37. The method of claim 36further comprising operating a detector and a processor in the probingdevice to determine a new wavelength of the new EM radiation.
 38. Themethod of claim 35 wherein the surface plasmon support materialcomprises a plurality of different material layers, each differentmaterial layer to absorb radiation at a different energy level.
 39. Amethod for making a radiation detection system comprising: positioningat least one fiber to receive radiation from a radiation source; forminga surface plasmon support material on portions of the at least one fiberand to receive the radiation from the radiation source that initiates asurface plasmon at an interface between the at least one fiber and thesurface plasmon support material; and coupling a probing device to theat least one fiber and to detect the surface plasmon, thereby defining asurface plasmon resonance (SPR) radiation detector.
 40. The method ofclaim 39 wherein the probing device comprises: an probe electromagnetic(EM) radiation source configured to emit probe EM radiation into the atleast one fiber, the probe EM radiation interacting with the surfaceplasmon and generating new EM radiation having a different wavelengththan the probe EM radiation resulting from the interaction; and an EMradiation detector coupled to the at least one fiber and configured todetect the new EM radiation.
 41. The method of claim 40 wherein theprobing device comprises a processor configured to determine awavelength of the new EM radiation.
 42. The method of claim 40 whereinthe probe EM radiation source comprises at least one of a visible EMradiation source, an ultraviolet (UV) EM radiation source, and aninfrared (IR) EM radiation source.
 43. The method of claim 39 whereinthe forming of the surface plasmon support material comprises at leastone of physical vapor deposition (PVD), chemical vapor deposition (CVD),plating, additive manufacturing, and ultrasonic bonding.
 44. The methodof claim 39 wherein the surface plasmon support material comprises aplurality of different material layers, each different material layer toabsorb radiation at a different energy level.